Tetrabenazine—the only approved therapy for chorea associated with Huntington disease (HD)—has variable metabolism, often requiring frequent dosing for symptom control. In a randomized placebo-controlled trial involving 90 patients with HD, Frank and colleagues assessed the safety and efficacy of deutetrabenazine—a novel form of tetrabenazine containing deuterium, which attenuates drug metabolism. The authors found that compared with placebo, deutetrabenazine resulted in improved motor signs at 12 weeks. In an Editorial, Geschwind and Paras discuss deutetrabenazine for treatment of Huntington disease.

In a multicenter randomized trial that enrolled 365 family decision makers for hospitalized adult patients with chronic critical illnesses requiring at least 7 days of mechanical ventilation, Carson and colleagues assessed the effect of palliative care clinician-led informational and emotional support meetings on family anxiety and depression. The authors report that compared with usual care, the palliative care-led meetings did not reduce anxiety or depression among patient decision makers. In an Editorial, White discusses strategies to support surrogate decision makers.

Walter and colleagues examined the association between a polygenic risk score for body mass index (BMI) and actual BMI in an analysis of data from 8788 US adults aged 50 years and older who were participating in the US Health and Retirement Study. The authors found that among adults born between 1900 and 1958, the magnitude of the association between a genetic risk score for BMI and calculated BMI was larger among those born in later cohorts—suggesting that known genetic variants for BMI are modified by obesogenic environments.

Wang and colleagues assessed the association between CYP2C19 genetic variants and clinical outcomes in 2933 Chinese patients with acute minor ischemic stroke or transient ischemic attack who were randomly assigned to receive clopidogrel combined with aspirin or aspirin alone. The authors report that through 90 days’ follow-up, clopidogrel with aspirin reduced the rate of new stroke only in the subgroup of patients who were not carriers of the CYP2C19 loss-of-function alleles.

Based on a review of US, Canadian, and European survey data (1947-2016), state and country databases, and death certificate studies, Emanuel and colleagues provide an overview of the legal status of euthanasia and physician-assisted suicide and related attitudes and practices. The authors report that euthanasia and physician-assisted suicide are increasingly being legalized but remain relatively rare and primarily involve patients with cancer. Existing data do not suggest abuse of these practices.

A 66-year-old man who had recently initiated treatment with azathioprine for autoimmune hepatitis presented with a 2-day history of fever, lethargy, arthralgias, and a painful rash on the extensor surfaces of his extremities. Laboratory findings included elevated levels of neutrophils and inflammatory markers. A patellar tap was performed and the fluid analysis showed a noninflammatory picture. What would you do next?

This JAMA Diagnostic Test Interpretation article presents the case of a 43-year-old woman with abnormal vaginal bleeding who was found to have endometrial cancer. Family history was significant for prostate cancer in her father and paternal grandfather. Results of tumor screening and genetic testing for Lynch syndrome are presented. An Editorial by Pasche and colleagues discusses Lynch syndrome testing.